Scattered across our solar system are small celestial bodies packed with water ice. Yes, our planet is covered in the stuff, but water is heavy and therefore expensive to launch into space. Therefore, to supply humans in space, where you have to bring everything you need with you, it makes sense to not use a terrestrial supply and utilize the water that's already out there.

Fortunately, as our technologies become more sophisticated, the trend these days is to envision exploiting in-situ resources if we are to establish a colony. That means that you live "off the land," so to speak, extracting the resources you need to survive. In the case of water, it is abundant in asteroids and comets across the solar system and researchers say asteroids could be the answer to the future of space exploration.

According to Phil Metzger, an associate in planetary science research with the Florida State Institute, past mining conferences have been focused on advocacy. With this one, however, the community was "organizing the process of getting it started," he told Seeker.

"It wasn't a bunch of people saying we ought to do it; that wasn't discussed because we are doing it now," he said. "We were focused on how do we do the job? The mining companies had come up with a list of questions for planetary scientists to understand the geology and the physics of asteroids, so that they can make their mining plans more specific and concrete."

Part of the spur in the community's side is Luxembourg's funding of several space mining companies, which Metzger says is likely due to their heritage in communications satellite investments. To save on fuel, there are proposals to have a space tug bring communications satellites into high Earth orbit - rather than using a rocket stage or other means - while the space tug is on its way to pick up the resources from a mined asteroid stored at an in-space propellant depot.

But this is all in a very early stage. The space mining startups in attendance at the conference were Planetary Resources, Deep Space Industries and TransAstra, which all made presentations on what they are working on today.

"Being a planetary geologist by training, it was exciting to interact with other planetary scientists to get outside perspectives on the types of data that would be necessary in a prospecting mission to sufficiently characterize an asteroid for later mining," Elizabeth Frank, who is at Planetary Resources, told Seeker.

Earlier this year, the company raised $21.1 million in Series A funding to implement an Earth observation program, which will use similar sensors to what will be used for asteroid mining. Planetary Resources is also launching demonstration satellites to test avionics, software and other items in space, close to home, before venturing out in the solar system. Luxembourg and Planetary Resources have also signed a memorandum of agreement to co-operate on work such as space hardware development and space services.

Similarly, Luxembourg is supporting the privately-funded Deep Space Industries as the company develops its own suite of spacecraft for prospecting asteroids. The company plans to launch an experimental small satellite called Prospector-X next year. It's also developing a spacecraft lander called Prospector-1, which could launch between 2019 and 2022 if the schedule holds.

TransAstra - whose CEO, Joel Sercel, receives some funding from NASA for various projects - discussed its optical mining asteroid resource extraction technology. Essentially, the way this mining would work is to enclose an asteroid in a large bag. Then, a solar concentrator would direct energy from the sun onto the asteroid. This would boil off water from the surface, which would be trapped inside the bag. This could later be collected and stored as ice.

Also, the company presented a rocket engine concept called Omnivore, which is designed to use almost any volatile gas or liquid as propellant, Sercel said in an e-mail to Seeker.

Testing the technology is one challenge, but the conference participants were also focused on figuring out the "to-do list" to define what is needed to make asteroid mining a reality, said conference participant Andy Rivkin, a scientist at the Johns Hopkins University Applied Research Laboratory who focuses on near-infrared spectroscopy of asteroids.

Close-up of the asteroid Vesta, as seen by NASA's Dawn mission. Vesta may be partly composed of water ice. |
Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Rivkin likened the process to what the planetary science community does every decade or so to figure out what to research next. Typically, when NASA looks into funding a particular mission (for example) it will look at the National Science Council's decadal survey to see what the priorities are. Europa was identified as a priority in the last decadal survey, which is helping to fuel NASA's interest in developing a Jupiter orbiter that will make several flybys of Europa in the 2030s, if it is approved for launch.

"NASA has also asked asteroid scientists to help define 'strategic knowledge gaps' in human exploration - things we need to know in order to safely send astronauts to asteroids but don't yet know," Rivkin told Seeker.

"Something similar for asteroid mining could be developed with community input, though obviously the nuances of how to handle proprietary work and do this to help for-profit companies would need to be worked out. I also suspect we'll try to have another meeting in the next year or two, after the mining companies have digested the presentations from this one and have developed the next set of questions they need answered."